The Leo Vertex (レオ・バーテックス Reo Bātekkusu), also known as a Shishi Type is an enemy of humanity, and the eleventh Vertex the Hero Club encounters. It is based on the constellation Leo the Lion. It is the strongest known Vertex.
The Leo Vertex is a ring connected by six spikes five of them being orange. It has another ring slightly out of the main ring and what almost seems to be claws sticking out. Its body opens in the center when it is summoning Stardust.
- In Washio Sumi's Chapter - Promise it was leading all 11 other vertex and Nogi Sonoko was forced to go Mankai twenty times in order to push them back
- In Yuki Yuna it was introduced in Episode 5 used to fuse the other vertex. It then came back in Episode 11 and 12 as a way to kill the Shinju and became "The Sun"
- Despite its strength as the strongest Vertex, it does not perform any attacks on its own and relies on its summons to perform its attacks.
- In the anime, it has been shown to be capable of the following:
- Combining Vertexes
- Summoning common Vertex as well as evolved Vertex
- Creating a massive fireball that could be compared to the sun, and required all the Hero Club's strength in order to just stop it.
- Also, at the end of Nogi Wakaba is a Hero, it was the Vertex responsible for causing the world to become its current appearance, a world of flames, by self-destructing. This also wiped out all 11 of the other evolved Vertex in the process.